Biomorphic propulsion system diving thunniform robotic fish

TL;DR

This paper presents a biomorphic robotic fish with a novel elastic tail propulsion system that mimics natural fish movement, demonstrating controllable oscillations and effective underwater locomotion through experimental testing.

Contribution

It introduces a new elastic chord-based tail propulsion system with controllable oscillations, designed using computational modeling, and validated through prototype experiments.

Findings

Velocity depends on tail oscillation amplitude and frequency

The system effectively mimics natural thunniform locomotion

Prototype tests confirm controllable and efficient underwater movement

Abstract

A biomorphic propulsion systemfor underwater robotic fish is presented. The system is based on a combination of an elastic chord with a tail fin fixed on it. The tail fin is connected to servomotor by two symmetric movable thrusts simulating muscle contraction. The propulsion system provides oscillatory tail movement with controllable amplitude and frequency. Tail oscillations results in translational movement of the robotic fish implementing the thunniform principle of locomotion. The shape of the body of the robotic fish and the tail fin were designed using computational model simulating virtual body in an aquatic medium. A prototype of robotic fish device was constructed and tested in experimental conditions. Dependencies of fish velocity on the amplitude and frequency of tail oscillations were analyzed.